Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * SMP support for ppc. | |
3 | * | |
4 | * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great | |
5 | * deal of code from the sparc and intel versions. | |
6 | * | |
7 | * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu> | |
8 | * | |
9 | * PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and | |
10 | * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
17 | ||
18 | #undef DEBUG | |
19 | ||
20 | #include <linux/config.h> | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/sched.h> | |
24 | #include <linux/smp.h> | |
25 | #include <linux/interrupt.h> | |
26 | #include <linux/delay.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/spinlock.h> | |
29 | #include <linux/cache.h> | |
30 | #include <linux/err.h> | |
31 | #include <linux/sysdev.h> | |
32 | #include <linux/cpu.h> | |
33 | #include <linux/notifier.h> | |
4b703a23 | 34 | #include <linux/topology.h> |
1da177e4 LT |
35 | |
36 | #include <asm/ptrace.h> | |
37 | #include <asm/atomic.h> | |
38 | #include <asm/irq.h> | |
39 | #include <asm/page.h> | |
40 | #include <asm/pgtable.h> | |
41 | #include <asm/prom.h> | |
42 | #include <asm/smp.h> | |
1da177e4 LT |
43 | #include <asm/time.h> |
44 | #include <asm/machdep.h> | |
45 | #include <asm/cputable.h> | |
46 | #include <asm/system.h> | |
bbeb3f4c | 47 | #include <asm/mpic.h> |
a7f290da | 48 | #include <asm/vdso_datapage.h> |
5ad57078 PM |
49 | #ifdef CONFIG_PPC64 |
50 | #include <asm/paca.h> | |
51 | #endif | |
52 | ||
1da177e4 | 53 | #ifdef DEBUG |
f9e4ec57 | 54 | #include <asm/udbg.h> |
1da177e4 LT |
55 | #define DBG(fmt...) udbg_printf(fmt) |
56 | #else | |
57 | #define DBG(fmt...) | |
58 | #endif | |
59 | ||
f9e4ec57 ME |
60 | int smp_hw_index[NR_CPUS]; |
61 | struct thread_info *secondary_ti; | |
62 | ||
1da177e4 LT |
63 | cpumask_t cpu_possible_map = CPU_MASK_NONE; |
64 | cpumask_t cpu_online_map = CPU_MASK_NONE; | |
65 | cpumask_t cpu_sibling_map[NR_CPUS] = { [0 ... NR_CPUS-1] = CPU_MASK_NONE }; | |
66 | ||
67 | EXPORT_SYMBOL(cpu_online_map); | |
68 | EXPORT_SYMBOL(cpu_possible_map); | |
69 | ||
5ad57078 | 70 | /* SMP operations for this machine */ |
1da177e4 LT |
71 | struct smp_ops_t *smp_ops; |
72 | ||
73 | static volatile unsigned int cpu_callin_map[NR_CPUS]; | |
74 | ||
1da177e4 LT |
75 | void smp_call_function_interrupt(void); |
76 | ||
77 | int smt_enabled_at_boot = 1; | |
78 | ||
cc532915 ME |
79 | static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL; |
80 | ||
cebf589c | 81 | #ifdef CONFIG_MPIC |
1da177e4 LT |
82 | int __init smp_mpic_probe(void) |
83 | { | |
84 | int nr_cpus; | |
85 | ||
86 | DBG("smp_mpic_probe()...\n"); | |
87 | ||
88 | nr_cpus = cpus_weight(cpu_possible_map); | |
89 | ||
90 | DBG("nr_cpus: %d\n", nr_cpus); | |
91 | ||
92 | if (nr_cpus > 1) | |
93 | mpic_request_ipis(); | |
94 | ||
95 | return nr_cpus; | |
96 | } | |
97 | ||
98 | void __devinit smp_mpic_setup_cpu(int cpu) | |
99 | { | |
100 | mpic_setup_this_cpu(); | |
101 | } | |
5ad57078 | 102 | #endif /* CONFIG_MPIC */ |
1da177e4 | 103 | |
5ad57078 | 104 | #ifdef CONFIG_PPC64 |
1da177e4 LT |
105 | void __devinit smp_generic_kick_cpu(int nr) |
106 | { | |
107 | BUG_ON(nr < 0 || nr >= NR_CPUS); | |
108 | ||
109 | /* | |
110 | * The processor is currently spinning, waiting for the | |
111 | * cpu_start field to become non-zero After we set cpu_start, | |
112 | * the processor will continue on to secondary_start | |
113 | */ | |
114 | paca[nr].cpu_start = 1; | |
0d8d4d42 | 115 | smp_mb(); |
1da177e4 | 116 | } |
5ad57078 | 117 | #endif |
1da177e4 | 118 | |
1da177e4 LT |
119 | void smp_message_recv(int msg, struct pt_regs *regs) |
120 | { | |
121 | switch(msg) { | |
122 | case PPC_MSG_CALL_FUNCTION: | |
123 | smp_call_function_interrupt(); | |
124 | break; | |
5ad57078 | 125 | case PPC_MSG_RESCHEDULE: |
1da177e4 LT |
126 | /* XXX Do we have to do this? */ |
127 | set_need_resched(); | |
128 | break; | |
1da177e4 | 129 | case PPC_MSG_DEBUGGER_BREAK: |
cc532915 ME |
130 | if (crash_ipi_function_ptr) { |
131 | crash_ipi_function_ptr(regs); | |
132 | break; | |
133 | } | |
134 | #ifdef CONFIG_DEBUGGER | |
1da177e4 LT |
135 | debugger_ipi(regs); |
136 | break; | |
cc532915 ME |
137 | #endif /* CONFIG_DEBUGGER */ |
138 | /* FALLTHROUGH */ | |
1da177e4 LT |
139 | default: |
140 | printk("SMP %d: smp_message_recv(): unknown msg %d\n", | |
141 | smp_processor_id(), msg); | |
142 | break; | |
143 | } | |
144 | } | |
145 | ||
146 | void smp_send_reschedule(int cpu) | |
147 | { | |
148 | smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE); | |
149 | } | |
150 | ||
151 | #ifdef CONFIG_DEBUGGER | |
152 | void smp_send_debugger_break(int cpu) | |
153 | { | |
154 | smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK); | |
155 | } | |
156 | #endif | |
157 | ||
cc532915 ME |
158 | #ifdef CONFIG_KEXEC |
159 | void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *)) | |
160 | { | |
161 | crash_ipi_function_ptr = crash_ipi_callback; | |
162 | if (crash_ipi_callback) { | |
163 | mb(); | |
164 | smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK); | |
165 | } | |
166 | } | |
167 | #endif | |
168 | ||
1da177e4 LT |
169 | static void stop_this_cpu(void *dummy) |
170 | { | |
171 | local_irq_disable(); | |
172 | while (1) | |
173 | ; | |
174 | } | |
175 | ||
176 | void smp_send_stop(void) | |
177 | { | |
178 | smp_call_function(stop_this_cpu, NULL, 1, 0); | |
179 | } | |
180 | ||
181 | /* | |
182 | * Structure and data for smp_call_function(). This is designed to minimise | |
183 | * static memory requirements. It also looks cleaner. | |
184 | * Stolen from the i386 version. | |
185 | */ | |
186 | static __cacheline_aligned_in_smp DEFINE_SPINLOCK(call_lock); | |
187 | ||
188 | static struct call_data_struct { | |
189 | void (*func) (void *info); | |
190 | void *info; | |
191 | atomic_t started; | |
192 | atomic_t finished; | |
193 | int wait; | |
194 | } *call_data; | |
195 | ||
5ad57078 PM |
196 | /* delay of at least 8 seconds */ |
197 | #define SMP_CALL_TIMEOUT 8 | |
1da177e4 LT |
198 | |
199 | /* | |
200 | * This function sends a 'generic call function' IPI to all other CPUs | |
201 | * in the system. | |
202 | * | |
203 | * [SUMMARY] Run a function on all other CPUs. | |
204 | * <func> The function to run. This must be fast and non-blocking. | |
205 | * <info> An arbitrary pointer to pass to the function. | |
206 | * <nonatomic> currently unused. | |
207 | * <wait> If true, wait (atomically) until function has completed on other CPUs. | |
208 | * [RETURNS] 0 on success, else a negative status code. Does not return until | |
209 | * remote CPUs are nearly ready to execute <<func>> or are or have executed. | |
210 | * | |
211 | * You must not call this function with disabled interrupts or from a | |
212 | * hardware interrupt handler or from a bottom half handler. | |
213 | */ | |
214 | int smp_call_function (void (*func) (void *info), void *info, int nonatomic, | |
215 | int wait) | |
216 | { | |
217 | struct call_data_struct data; | |
218 | int ret = -1, cpus; | |
5ad57078 | 219 | u64 timeout; |
1da177e4 LT |
220 | |
221 | /* Can deadlock when called with interrupts disabled */ | |
222 | WARN_ON(irqs_disabled()); | |
223 | ||
224 | data.func = func; | |
225 | data.info = info; | |
226 | atomic_set(&data.started, 0); | |
227 | data.wait = wait; | |
228 | if (wait) | |
229 | atomic_set(&data.finished, 0); | |
230 | ||
231 | spin_lock(&call_lock); | |
232 | /* Must grab online cpu count with preempt disabled, otherwise | |
233 | * it can change. */ | |
234 | cpus = num_online_cpus() - 1; | |
235 | if (!cpus) { | |
236 | ret = 0; | |
237 | goto out; | |
238 | } | |
239 | ||
240 | call_data = &data; | |
0d8d4d42 | 241 | smp_wmb(); |
1da177e4 LT |
242 | /* Send a message to all other CPUs and wait for them to respond */ |
243 | smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_CALL_FUNCTION); | |
244 | ||
5ad57078 PM |
245 | timeout = get_tb() + (u64) SMP_CALL_TIMEOUT * tb_ticks_per_sec; |
246 | ||
1da177e4 | 247 | /* Wait for response */ |
1da177e4 LT |
248 | while (atomic_read(&data.started) != cpus) { |
249 | HMT_low(); | |
5ad57078 | 250 | if (get_tb() >= timeout) { |
1da177e4 LT |
251 | printk("smp_call_function on cpu %d: other cpus not " |
252 | "responding (%d)\n", smp_processor_id(), | |
253 | atomic_read(&data.started)); | |
254 | debugger(NULL); | |
255 | goto out; | |
256 | } | |
257 | } | |
258 | ||
259 | if (wait) { | |
1da177e4 LT |
260 | while (atomic_read(&data.finished) != cpus) { |
261 | HMT_low(); | |
5ad57078 | 262 | if (get_tb() >= timeout) { |
1da177e4 LT |
263 | printk("smp_call_function on cpu %d: other " |
264 | "cpus not finishing (%d/%d)\n", | |
265 | smp_processor_id(), | |
266 | atomic_read(&data.finished), | |
267 | atomic_read(&data.started)); | |
268 | debugger(NULL); | |
269 | goto out; | |
270 | } | |
271 | } | |
272 | } | |
273 | ||
274 | ret = 0; | |
275 | ||
5ad57078 | 276 | out: |
1da177e4 LT |
277 | call_data = NULL; |
278 | HMT_medium(); | |
279 | spin_unlock(&call_lock); | |
280 | return ret; | |
281 | } | |
282 | ||
283 | EXPORT_SYMBOL(smp_call_function); | |
284 | ||
285 | void smp_call_function_interrupt(void) | |
286 | { | |
287 | void (*func) (void *info); | |
288 | void *info; | |
289 | int wait; | |
290 | ||
291 | /* call_data will be NULL if the sender timed out while | |
292 | * waiting on us to receive the call. | |
293 | */ | |
294 | if (!call_data) | |
295 | return; | |
296 | ||
297 | func = call_data->func; | |
298 | info = call_data->info; | |
299 | wait = call_data->wait; | |
300 | ||
301 | if (!wait) | |
302 | smp_mb__before_atomic_inc(); | |
303 | ||
304 | /* | |
305 | * Notify initiating CPU that I've grabbed the data and am | |
306 | * about to execute the function | |
307 | */ | |
308 | atomic_inc(&call_data->started); | |
309 | /* | |
310 | * At this point the info structure may be out of scope unless wait==1 | |
311 | */ | |
312 | (*func)(info); | |
313 | if (wait) { | |
314 | smp_mb__before_atomic_inc(); | |
315 | atomic_inc(&call_data->finished); | |
316 | } | |
317 | } | |
318 | ||
1da177e4 LT |
319 | extern struct gettimeofday_struct do_gtod; |
320 | ||
321 | struct thread_info *current_set[NR_CPUS]; | |
322 | ||
323 | DECLARE_PER_CPU(unsigned int, pvr); | |
324 | ||
325 | static void __devinit smp_store_cpu_info(int id) | |
326 | { | |
327 | per_cpu(pvr, id) = mfspr(SPRN_PVR); | |
328 | } | |
329 | ||
330 | static void __init smp_create_idle(unsigned int cpu) | |
331 | { | |
332 | struct task_struct *p; | |
333 | ||
334 | /* create a process for the processor */ | |
335 | p = fork_idle(cpu); | |
336 | if (IS_ERR(p)) | |
337 | panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p)); | |
5ad57078 | 338 | #ifdef CONFIG_PPC64 |
1da177e4 | 339 | paca[cpu].__current = p; |
5ad57078 | 340 | #endif |
1da177e4 | 341 | current_set[cpu] = p->thread_info; |
5ad57078 | 342 | p->thread_info->cpu = cpu; |
1da177e4 LT |
343 | } |
344 | ||
345 | void __init smp_prepare_cpus(unsigned int max_cpus) | |
346 | { | |
347 | unsigned int cpu; | |
348 | ||
349 | DBG("smp_prepare_cpus\n"); | |
350 | ||
351 | /* | |
352 | * setup_cpu may need to be called on the boot cpu. We havent | |
353 | * spun any cpus up but lets be paranoid. | |
354 | */ | |
355 | BUG_ON(boot_cpuid != smp_processor_id()); | |
356 | ||
357 | /* Fixup boot cpu */ | |
358 | smp_store_cpu_info(boot_cpuid); | |
359 | cpu_callin_map[boot_cpuid] = 1; | |
360 | ||
1da177e4 LT |
361 | max_cpus = smp_ops->probe(); |
362 | ||
363 | smp_space_timers(max_cpus); | |
364 | ||
365 | for_each_cpu(cpu) | |
366 | if (cpu != boot_cpuid) | |
367 | smp_create_idle(cpu); | |
368 | } | |
369 | ||
370 | void __devinit smp_prepare_boot_cpu(void) | |
371 | { | |
372 | BUG_ON(smp_processor_id() != boot_cpuid); | |
373 | ||
374 | cpu_set(boot_cpuid, cpu_online_map); | |
5ad57078 | 375 | #ifdef CONFIG_PPC64 |
1da177e4 | 376 | paca[boot_cpuid].__current = current; |
5ad57078 | 377 | #endif |
1da177e4 LT |
378 | current_set[boot_cpuid] = current->thread_info; |
379 | } | |
380 | ||
381 | #ifdef CONFIG_HOTPLUG_CPU | |
382 | /* State of each CPU during hotplug phases */ | |
383 | DEFINE_PER_CPU(int, cpu_state) = { 0 }; | |
384 | ||
385 | int generic_cpu_disable(void) | |
386 | { | |
387 | unsigned int cpu = smp_processor_id(); | |
388 | ||
389 | if (cpu == boot_cpuid) | |
390 | return -EBUSY; | |
391 | ||
1da177e4 | 392 | cpu_clear(cpu, cpu_online_map); |
799d6046 | 393 | #ifdef CONFIG_PPC64 |
a7f290da | 394 | vdso_data->processorCount--; |
1da177e4 | 395 | fixup_irqs(cpu_online_map); |
094fe2e7 | 396 | #endif |
1da177e4 LT |
397 | return 0; |
398 | } | |
399 | ||
400 | int generic_cpu_enable(unsigned int cpu) | |
401 | { | |
402 | /* Do the normal bootup if we haven't | |
403 | * already bootstrapped. */ | |
404 | if (system_state != SYSTEM_RUNNING) | |
405 | return -ENOSYS; | |
406 | ||
407 | /* get the target out of it's holding state */ | |
408 | per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; | |
0d8d4d42 | 409 | smp_wmb(); |
1da177e4 LT |
410 | |
411 | while (!cpu_online(cpu)) | |
412 | cpu_relax(); | |
413 | ||
094fe2e7 | 414 | #ifdef CONFIG_PPC64 |
1da177e4 LT |
415 | fixup_irqs(cpu_online_map); |
416 | /* counter the irq disable in fixup_irqs */ | |
417 | local_irq_enable(); | |
094fe2e7 | 418 | #endif |
1da177e4 LT |
419 | return 0; |
420 | } | |
421 | ||
422 | void generic_cpu_die(unsigned int cpu) | |
423 | { | |
424 | int i; | |
425 | ||
426 | for (i = 0; i < 100; i++) { | |
0d8d4d42 | 427 | smp_rmb(); |
1da177e4 LT |
428 | if (per_cpu(cpu_state, cpu) == CPU_DEAD) |
429 | return; | |
430 | msleep(100); | |
431 | } | |
432 | printk(KERN_ERR "CPU%d didn't die...\n", cpu); | |
433 | } | |
434 | ||
435 | void generic_mach_cpu_die(void) | |
436 | { | |
437 | unsigned int cpu; | |
438 | ||
439 | local_irq_disable(); | |
440 | cpu = smp_processor_id(); | |
441 | printk(KERN_DEBUG "CPU%d offline\n", cpu); | |
442 | __get_cpu_var(cpu_state) = CPU_DEAD; | |
0d8d4d42 | 443 | smp_wmb(); |
1da177e4 LT |
444 | while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE) |
445 | cpu_relax(); | |
446 | ||
094fe2e7 | 447 | #ifdef CONFIG_PPC64 |
1da177e4 | 448 | flush_tlb_pending(); |
094fe2e7 | 449 | #endif |
1da177e4 LT |
450 | cpu_set(cpu, cpu_online_map); |
451 | local_irq_enable(); | |
452 | } | |
453 | #endif | |
454 | ||
455 | static int __devinit cpu_enable(unsigned int cpu) | |
456 | { | |
457 | if (smp_ops->cpu_enable) | |
458 | return smp_ops->cpu_enable(cpu); | |
459 | ||
460 | return -ENOSYS; | |
461 | } | |
462 | ||
463 | int __devinit __cpu_up(unsigned int cpu) | |
464 | { | |
465 | int c; | |
466 | ||
5ad57078 | 467 | secondary_ti = current_set[cpu]; |
1da177e4 LT |
468 | if (!cpu_enable(cpu)) |
469 | return 0; | |
470 | ||
471 | if (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)) | |
472 | return -EINVAL; | |
473 | ||
1da177e4 LT |
474 | /* Make sure callin-map entry is 0 (can be leftover a CPU |
475 | * hotplug | |
476 | */ | |
477 | cpu_callin_map[cpu] = 0; | |
478 | ||
479 | /* The information for processor bringup must | |
480 | * be written out to main store before we release | |
481 | * the processor. | |
482 | */ | |
0d8d4d42 | 483 | smp_mb(); |
1da177e4 LT |
484 | |
485 | /* wake up cpus */ | |
486 | DBG("smp: kicking cpu %d\n", cpu); | |
487 | smp_ops->kick_cpu(cpu); | |
488 | ||
489 | /* | |
490 | * wait to see if the cpu made a callin (is actually up). | |
491 | * use this value that I found through experimentation. | |
492 | * -- Cort | |
493 | */ | |
494 | if (system_state < SYSTEM_RUNNING) | |
495 | for (c = 5000; c && !cpu_callin_map[cpu]; c--) | |
496 | udelay(100); | |
497 | #ifdef CONFIG_HOTPLUG_CPU | |
498 | else | |
499 | /* | |
500 | * CPUs can take much longer to come up in the | |
501 | * hotplug case. Wait five seconds. | |
502 | */ | |
503 | for (c = 25; c && !cpu_callin_map[cpu]; c--) { | |
504 | msleep(200); | |
505 | } | |
506 | #endif | |
507 | ||
508 | if (!cpu_callin_map[cpu]) { | |
509 | printk("Processor %u is stuck.\n", cpu); | |
510 | return -ENOENT; | |
511 | } | |
512 | ||
513 | printk("Processor %u found.\n", cpu); | |
514 | ||
515 | if (smp_ops->give_timebase) | |
516 | smp_ops->give_timebase(); | |
517 | ||
518 | /* Wait until cpu puts itself in the online map */ | |
519 | while (!cpu_online(cpu)) | |
520 | cpu_relax(); | |
521 | ||
522 | return 0; | |
523 | } | |
524 | ||
525 | ||
526 | /* Activate a secondary processor. */ | |
527 | int __devinit start_secondary(void *unused) | |
528 | { | |
529 | unsigned int cpu = smp_processor_id(); | |
530 | ||
531 | atomic_inc(&init_mm.mm_count); | |
532 | current->active_mm = &init_mm; | |
533 | ||
534 | smp_store_cpu_info(cpu); | |
5ad57078 | 535 | set_dec(tb_ticks_per_jiffy); |
e4d76e1c | 536 | preempt_disable(); |
1da177e4 LT |
537 | cpu_callin_map[cpu] = 1; |
538 | ||
539 | smp_ops->setup_cpu(cpu); | |
540 | if (smp_ops->take_timebase) | |
541 | smp_ops->take_timebase(); | |
542 | ||
543 | spin_lock(&call_lock); | |
544 | cpu_set(cpu, cpu_online_map); | |
545 | spin_unlock(&call_lock); | |
546 | ||
547 | local_irq_enable(); | |
548 | ||
549 | cpu_idle(); | |
550 | return 0; | |
551 | } | |
552 | ||
553 | int setup_profiling_timer(unsigned int multiplier) | |
554 | { | |
555 | return 0; | |
556 | } | |
557 | ||
558 | void __init smp_cpus_done(unsigned int max_cpus) | |
559 | { | |
560 | cpumask_t old_mask; | |
561 | ||
562 | /* We want the setup_cpu() here to be called from CPU 0, but our | |
563 | * init thread may have been "borrowed" by another CPU in the meantime | |
564 | * se we pin us down to CPU 0 for a short while | |
565 | */ | |
566 | old_mask = current->cpus_allowed; | |
567 | set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid)); | |
568 | ||
569 | smp_ops->setup_cpu(boot_cpuid); | |
570 | ||
571 | set_cpus_allowed(current, old_mask); | |
4b703a23 AB |
572 | |
573 | dump_numa_cpu_topology(); | |
1da177e4 LT |
574 | } |
575 | ||
576 | #ifdef CONFIG_HOTPLUG_CPU | |
577 | int __cpu_disable(void) | |
578 | { | |
579 | if (smp_ops->cpu_disable) | |
580 | return smp_ops->cpu_disable(); | |
581 | ||
582 | return -ENOSYS; | |
583 | } | |
584 | ||
585 | void __cpu_die(unsigned int cpu) | |
586 | { | |
587 | if (smp_ops->cpu_die) | |
588 | smp_ops->cpu_die(cpu); | |
589 | } | |
590 | #endif |